Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
The use of advanced robot manipulators in manufacturing is increasing. Robot manipulators may not only be used in the assembly of products, such as electronic devices and cars, but may also be used to perform processing steps such as welding and painting. For the latter application, general-purpose robot manipulators may handle custom tools designed for these processing steps.
A key skill of a robot manipulator is its ability to handle objects by means of a robot hand or robotic gripper. Robotic grippers exist in many configurations and their main goal is to be able to hold an object in a stable grasp even under disturbing forces acting on the object. Robot grasps can be analyzed and one of the physical constraints that defines a stable grasp is force closure. Force closure occurs when the forces exerted on an object by the fingers of a robotic gripper sum to zero. To achieve force closure the direction and magnitude of the forces exerted by the individual fingers on the grasp points of the object need to have a specific direction and magnitude, respectively, which is a challenging process for a robot manipulator.